human anatomy chapter 5
Describe the lunula.
it is the half-moon shaped region at the proximal end of the nail bed.
Which layer of the epidermis contains dark staining clusters of keratohyalin?
stratum granulosum
The dermis lies deep to the epidermis and is composed of _____.
connective tissue
The reticular layer of the dermis may best be described as ______.
dense irregular connective tissue
Which structure nourishes the hair cells?
dermal papilla
Friction ridges are the external expression of the ______.
dermal papillae
In some areas of the body the boundary between the dermis and epidermis is irregular. The wavy upward projections of the dermis are called ______.
dermal papillae
Cells in the stratum spinosum are nourished by blood vessels located in the ______.
dermis
Freckle color, size and number are influenced by ______.
exposure to sunlight and heredity
The distal portion of the nail plate becomes the _________ edge.
free
The distal portion of the nail plate becomes the ________.
free edge
Fingerprints are caused by which of the following?
friction ridges
Hair and nails are composed of hard keratin while the stratum corneum is mostly soft keratin. The difference is _______.
hard keratin is compact and crosslinked
Which of the following tissue types are found in the dermal layer of the skin?
-connective tissue -muscular tissue -nervous tissue -epithelial tissue
Functions of the skin include which of the following?
-resistance to trauma and infection -water retention -vitamin d synthesis -sensation -thermoregulation -nonverbal communication -sensory reception -protection of ultraviolet light
List the layers of the epidermis in order of deepest to most superficial.
-stratum basale -stratum spinosum -stratum granulosum -stratum lucidum -stratum corneum
List the layers of the epidermis in order of most superficial to deepest.
-stratum corneum -stratum lucidum -stratum granulosum -stratum spinosum -stratum basale
The subcutaneous layer is ______.
a layer of areolar and adipose tissue below the dermis
Which of the following describes the dermal papilla that is associated with hair?
an extension of the vascular system into the hair bulb
Cutaneous glands found in the groin, axilla, areolar, and beard area are classified as ____________ sweat glands
apocrine
Identify the type of glands that are found in the groin and areola regions.
apocrine
The epidermis, like all epithelial tissue, lacks ______.
blood vessels
What are the three zones of a hair?
bulb, shaft, root
The eponychium is commonly called the ______.
cuticle
What are the three concentric regions of the hair from the outside to the inside?
cuticle, cortex, medulla
stratum spinosum and stratum granulosum=
dendritic cells
Which of the following best describes hair?
dead, keratinized cells
Hair and nails are composed of ______.
dead, keratinized epidermal cells
Cells of the epidermis that stand guard against pathogens that breach the surface of the skin are ______.
dendritic cells
defend against microbes
dendritic cells
in which location would you EXPECT to find flexion lines?
digits, palms, wrists, elbows, knee, and other places
The acid mantle of the skin helps to ______.
discourage the growth of bacteria and fungi
Describe a mole.
elevated patch of melanized skin
Downward extensions of the epidermis at the dermis and epidermal boundary are called ______.
epidermal ridges
The epithelial root sheath of the hair follicle originates in the ______.
epidermis
The hyponychium is the ______.
epidermis of the nail bed
Which of the following sequences correctly describes the layers of the integument from the most superficial to the deepest layers?
epidermis, dermis, subcutaneous
what are the two layers of the hair follicle?
epithelial root sheath and connective tissue root sheath
The area of dead skin that overhangs the lunula is called the ______.
eponychium
True or false: During a manicure, it is the nail matrix that is trimmed.
false
True or false: Freckles are patches of keratinocytes that result from exposure to sunlight.
false
True or false: Melanocytes are the only darkly pigmented cells in the epidermis.
false
True or false: The epidermis is composed of keratinized simple squamous epithelium.
false
True or false: The follicle is a zone of a hair.
false
The epidermis of the nail bed is called the ______.
hyponychium
Flexion lines occur ______.
in the skin where it folds around flexing joints
The hair and nails are composed primarily of ______.
keratin
The epidermis is composed of ______.
keratinized stratified squamous epithelium
Keratin, a protein associated with the skin, is produced by ______.
keratinocytes
One type of epidermal cell produces a protein that increases the durability of the skin. What cells are these?
keratinocytes
all layers of the epidermis=
keratinocytes
produces the tough structural protein of the epidermis
keratinocytes
Thick skin contains a clear layer packed with eleidin called the stratum ____.
lucidum
The crescent-shaped region at the proximal end of the nail bed consists is called the ______.
lunula
A hair is formed by mitotic cells in which region?
matrix
At the center of each hair is a loosely arranged core of cells and air spaces. This region is called the ______.
medulla
deposit pigment in the interstitial spaces in the epidermis
melanocytes
produces the pigment that shields the DNA from ultraviolet radiation
melanocytes
stratum basale=
melanocytes and stem cells
A elevated patch of melanized skin is a(n) _____________
mole
Which term refers to the portion of a fingernail or toenail that is attached to the tip of the digit (finger)?
nail body
The skin surrounding the nail is called the ______.
nail fold
The part of the nail which extends proximally under the skin is called the _____.
nail root
Sebaceous glands produce secretion that is characterized as which of the following?
oily
What are the two zones of the dermis?
papillary and reticular layer
The dermis consists of two zones: the more superficial _________ layer and the deeper ____________ layer.
papillary; reticular
Which of these layers is the deepest layer of the dermis and composed of dense irregular connective tissue?
reticular layer
The part of the nail which extends proximally under the skin is called the nail ____________
root
Name the oily component of the secretion of the sebaceous glands.
sebum
Which portion of the hair is found above the epidermis?
shaft
You visit your local hairdresser for a hair cut. What anatomic structure is being cut?
shaft
What are piloerector muscles?
smooth muscle fibers attached to the connective tissue root sheath
Which layer of the epidermis is seen only in thick skin?
stratum lucidum
touch receptors
tactile disc
What happens when piloerector muscles contract?
the hair "stands on end"
Which portion of the hair lies between the bulb and the shaft?
the hair root
The hair root is ______.
the portion of the hair above the bulb, but still in the skin
What is the hair matrix?
the region of actively mitotic cells above the papilla
Dermal papillae are ______.
the upward projections of the dermis at the dermis-epidermis boundary
The stratum granulosum can best be described as:
three to five layers of keratinocytes filled with clusters of keratohyalin
in which location would you NOT EXPECT to find flexion lines?
umbilicus